Magnetic Door Switch – Normally Closed


Availability: In Stock

This simple door switch is based on a magnet and a reed switch. The magnet and the reed switch are both encased in ABS plastic with handy mounting holes. These sensors are commonly seen in consumer alarm systems and make an ideal addition to any Arduino or Raspberry Pi based alarm system, door monitor, etc.


SKU: SEN-136 Mfg Part Number: MC-38 Category: Tags: , , ,


The reed switch is simply a magnetic activated switch, as long as a magnet is close to it the reed switch will remain open. This switch should open when the included magnet is within 15mm of the switch. Once the magnet is removed, the switch closes, completing the circuit. The reed switch can handle a maximum of 100mA and a maximum of 200VDC.

Each half of the sensor can be mounted with the included adhesive backing. Alternatively, there are also screw holes. The mounting holes are 18.2mm apart (measured center to center) on both the sensor and the magnet. The housings for both the sensor and the magnet 27.5 x 13.6 x 9mm each, with the sensor including a 300mm wire leads.

If you need the opposite logic, we also carry a Normally Open version as well.



  • Dimensions (Housing): 27.5 x 13.6 x 9mm
  • Wire Length: 300mm
  • Maximum Current: 100mA
  • Maximum Voltage: 200VDC
  • Magnet Range: approx. 15mm
  • Switch Type: Normally Closed

Package Contents

  • 1 x Magnetic Door Switch - Normally Closed

May We Also Suggest…

Magnetic Door Switch – Normally Open
Price: $4.00
Reed Switch
Price: $2.95
Reed Switch – Basic
Price: $0.30


  Difficulty Level

Soldering Skill: N/A
Prototyping Skill: Beginner
Programming Skill: N/A

  Product Certifications

  Product Attributes

Weight: 11 g
Termination Style:

Wire Leads

Cable Length:

300mm / ~1'

  Warranty Policy

This product has a 30 Day Warranty from the date of delivery. The item must not be modified, abused, incorrectly hooked up, or used for purposes outside the original scope of design.

  Return Policy

This product is returnable Within 14 Days of delivery for a store credit. Item must be unopened, unused, and in re-saleable condition.

More Information:
For more information on our Warranty and Return Policies, please consult our   Terms of Service


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